//
//  UIColor+Hex.m
//  我的优选  页面
//
//  Created by 贾宸穆 on 15/9/1.
//  Copyright (c) 2015年 admin. All rights reserved.
//

#import "UIColor+Hex.h"

@implementation UIColor (Hex)
+ (UIColor *)colorWithHexString:(NSString *)color alpha:(CGFloat)alpha
{
  //删除字符串中的空格
  NSString *cString = [[color stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];
  // String should be 6 or 8 characters
  if ([cString length] < 6)
  {
    return [UIColor clearColor];
  }
  // strip 0X if it appears
  //如果是0x开头的，那么截取字符串，字符串从索引为2的位置开始，一直到末尾
  if ([cString hasPrefix:@"0X"])
  {
    cString = [cString substringFromIndex:2];
  }
  //如果是#开头的，那么截取字符串，字符串从索引为1的位置开始，一直到末尾
  if ([cString hasPrefix:@"#"])
  {
    cString = [cString substringFromIndex:1];
  }
  if ([cString length] != 6)
  {
    return [UIColor clearColor];
  }
  
  // Separate into r, g, b substrings
  NSRange range;
  range.location = 0;
  range.length = 2;
  //r
  NSString *rString = [cString substringWithRange:range];
  //g
  range.location = 2;
  NSString *gString = [cString substringWithRange:range];
  //b
  range.location = 4;
  NSString *bString = [cString substringWithRange:range];
  
  // Scan values
  unsigned int r, g, b;
  [[NSScanner scannerWithString:rString] scanHexInt:&r];
  [[NSScanner scannerWithString:gString] scanHexInt:&g];
  [[NSScanner scannerWithString:bString] scanHexInt:&b];
  return [UIColor colorWithRed:((float)r / 255.0f) green:((float)g / 255.0f) blue:((float)b / 255.0f) alpha:alpha];
}

//默认alpha值为1
+ (UIColor *)colorWithHexString:(NSString *)color
{
  return [self colorWithHexString:color alpha:1.0f];
}
@end
